Speakers/Brightness Keys not functioning

There is a checkbox on the keyboard preferences that I believe controls whether the f1-f12 keys control application or hardware. Make sure that it is cleared (system prefs->keyboard & mouse, the keyboard 'tab'...)

MacBook 2.0GHz (white) Mac OS X (10.4.7)

I am also having this problem. I have no idea what causes it, and it's solved by a restart. The preference checkbox for handing the function keys to the application is not checked.

I have installed all the updates (current to 10.4.8). I first observed this problem about a week ago (before 10.4.8) but I can't necessarily relate it to a specific maintenance event.

I'm having the same issue. The brightness, volume, and num lock keys suddenly do not function. I've tried flipping the state of the preference checkbox, zapped PRAM, restarted - all to no avail. Any other ideas what might be amiss or how to fix this?

I have the same problem on my brand new Macbook. was wondering if you had solved the problem in one way or another.

Have you tried this ? http://docs.info.apple.com/article.html?artnum=303319

I'm stuck with this too. Tried everything - next stop will be at Apple for a logic board replacement.

So I just got a refurbed macbook core 2 duo today from Apple.... and I have this same problem of the brightness and sound keys not functioning. Has anyone figured out what this problem might be? I'm really upset something like this got by "Apple's stringent refurbishment process prior to being offered for sale."

Any suggestions from anyone that successfully resolved this issue?

After an unproductive conversation with tech support, I ultimately just decided for myself to do an archive and install of OS X.... fixed the problem entirely.

Not a quick fix, but the easiest that will preserve all the settings with minimal impact on operation. Anyone else that has had a problem with the brightness and sound keys not function, this probably is your best bet.

Can you give directions on how to do the archive and install procedure, or else a link to somewhere that can?

I just got my Macbook replaced, and I don't want to have to send this new one in right away.

Since this seems to be a problem that many people are having, is there any way we can let Apple know about it?

I think that they're unaware that the issue is this widespread. When I talked to Apple Support about it, they were oblivious to the problem and just suggested I take it in to a retail store for the Geniuses to look at.

Has anyone found how to solve this problem without Archive and Install?

Just boot from the first install CD (insert the CD, turn off the computer, hold down C while booting), the one labeled (I think) Mac OS X Install Disk 1 (or something like that). It'll ask you what language you want to use. In the next window I think, it asks you if you want to do an erase and install or archive and install. The obvious choice would be archive and install. It's a good idea to backup your data to an external HDD just in case anything goes wrong.

Do try jrsmobile's advice of checking the Preference Pane settings.